Analysis of pemoline in serum by high performance liquid chromatography: clinical application to optimize treatment...

The analysis of pemoline (2-imino-5-phenyl-4-oxazolidine) by a rapid, sensitive, and specific high performance liquid chromatographic assay using ultraviolet detection is described. Only 100 microliters of plasma or serum is required. Analytical recoveries of 88% for pemoline and 93% for the internal standard (4-methylprimidone) are obtained by this procedure. Between-day precision studies of serum controls containing 10.2, 2.0, and 0.5 mg pemoline/liter produce coefficients of variation of 6.2, 9.4, and 16.2%, respectively. A clinical study of 28 children treated with pemoline demonstrated a linear relationship between drug dose and serum concentrations with an apparent therapeutic range falling between 1.7 and 7.0 mg/liter. These serum concentrations were achieved at drug dosages between 37.5 and 112.5 mg/day.